The effects of continuous flow microwave treatment and conventional heating on the nutritional value of milk as shown by influence on vitamin B1 retention

The effects of continuous now microwave treatment and conventional heating (using a plate heat exchanger) on the nutritional value of raw mill; was estimated by measurement of the Vitamin B-1 retention. Microwave heating, without a holding phase, did not modify the vitamin B-1 content of milk, whereas analogous treatment carried out with the plate heat exchanger led to a loss of this vitamin. A holding phase caused a similar loss of vitamin B-1 in milk heated using either system. These results indicate that continuous flow microwave treatment of milk compares favourably with conventional heating because it produce less destruction of vitamin B-1 in milk. This could be attributed to the shorter time taken to reach the final temperature and the lack of hot surfaces in contact with the milk in the case of the microwave system.